Duckunder or lifting section.

"Keith J Patrick" wrote

Depends upon how capable you are of ducking-under. As I've got older I find it harder to do, so would personally go for a lifting section.

John.

As you get older, duckunders seem to get lower.

Well, I'm already that. or at least feel it some of the time. Are lifting sections the best, or removeable ?, I've seen one in an American magazine which was hinged to the side.

A friend works for a well-known Chinese owned manufacturer of live steam and electric G-gauge models, in their American HQ.

He set up a test track around the walls of the workshop, using a through truss bridge from another manufacturer, that he just dropped into place, with a length of flex to supply track power.

If it were me, I'd want some kind of electrical protection to turn the track power off when it was lifted but that shouldn't be too difficult.

Duckunders should be avoided. Someone is sure to come up for air too soon, and damage the layout (not to mention his or her back.)

Depending on the space inside the layout, a gate might work. But liftout or gate, the key is reliable mating of layout structure, then rail alignment is automatic. The ones that seem to work best (of the few Ive actually seen) have metal plates and pins with close clearances to join the movable sections. I've also seen a couple of scale models of lifting/rolling bridges of a suitable size. Impressive, but need to be around 300 scale foot (OO) span, which means they'll dominate the layout.

HTH

Feed the sections either side from the lift out section so if lift out isn't there the tracks leading to it are not energised.

If you're getting on in years a hinged section is preferable - imagine the frustration of not remembering where you left the bridge! Up, down, or sideways? It depends on your space and layout. Personally I'd avoid the gate swinging type due to the possibility of it getting out of shape when someone leans on it. Upwards probably gives the best protection for the track and any scenic detailing.

"Keith J Patrick" wrote in news: snipped-for-privacy@bt.com:

I was faced with eh same conundrum as yourself when laying out my garage layout. Only 44 inches from the floor in my case though 2 and a bit feet wide. I had initially envisioned a lifting section but a last minute change of plan saw a turntable placed on what would be the lifting section. Rather than risk damage and lots of plugs and sockets for the electrics I decided to make it a fixed duck under.

I?m 41 and don?t have any problems, baring in mind the actual clearance is only around 40 inches (because of under board electrics etc). You pays your money and you makes your choice, if I hadn?t any junctions etc on the section I?d have stayed with Plan A but as I have Plan B works for me ...

If you're hingeing upwards, remember that the centre line of the hinge pins or the pivot must be on the level of the rail head. Downwards hingeing would not need this, but may be awkward to handle and to lock in closed position. Do you intend to have any scenery on this lifting section, if so, this may make upwards hingeing difficult. Regards, Bill.

Scenery, yes, and two tracks, one descending and one ascending. This is what was making me hesitate about a lifting/hinged section, and as to whether it was better to live with a duckunder.

Not necessarily. I've seen upward lifting sections where the hinges were mounted on blocks above the rail head. This was done to provide clearance for a through bridge on the lift-up section.

Besides exposing any scenery on the section to passing knees (knobbly ones are especially destructive. ;-))

[...]

On Sun, 5 Aug 2007 15:50:55 +0100, "Keith J Patrick" said in :

Having travelled across the Mawddach Estuary bridge a couple of times this week, I am inspired to try a pivot in the vertical plane for the section on the new layout I am planning. It will be about

6ft long and landscaped, so two 3ft pivoted sections might well be the easiest way to do it.

I also had a "steel" bridge that just lifted out - no hinges or anything - on the old layout, that worked tolerably well too.

Guy

On Sun, 5 Aug 2007 15:50:55 +0100, "Keith J Patrick" said in :

I'd go with duckunder 'cos in the n gauge layout I had 20 years ago, the tolerances of a lift out section (after several lift outs) were grew to more than the width of the rail (one side not the whole sleeper caboodle!). Net result...train comes along and derails.

Lift out is probably OK for the first 20 times you do it. Then it wears.

On Fri, 24 Aug 2007 20:23:01 +0100, "Peter" said in :

Deep ends I reckon. For alignment, I used some of those plastic mounting blocks with little pegs that go in holes, many operations later the thing still lined up perfectly, and if it had worn I could simply have replaced the blocks with new ones.

Guy

The message from "Peter" contains these words:

The lift up section on my line has been in regular use for over 20 years without any problems. It was designed to have some leeway to allow for movement in the timber (2 x 1 framing and 3/8 ply trackbed): a set of plastic "shims" which can slide under the bearing surface to help the rails to line up vertically.

Much more important is the bolt which locks the door when the lifting section is down...

We rehung the door so that it opened outwards into the landing.

I had a lot of movement in the timber, but did not have any shims or bolts to lock the lifting section once in place.

In all the articles I've read, plastic and/or metal plugs, pins, shims, blocks, etc, were used to ensure precise alignment every time the movable section was opened. In addition, either the rails one each side of the gaps was soldered to screws, metal plates, or PC ties (sleepers). And alternative was a short section of track inserted to bridge the gap, using rail joiners to line up the rail ends. One builder used dress snaps soldered to screws in the fixed baseboard and to the underside of the bridging rails to ensure electrical contact. All of them used some kind of interlocking switch to isolate the approach tracks when the movable section was opened.